The Initialization File

Once invoked, the default prolog looks in your home directory for a file named prolog.ini, and if it finds one, loads it. Stand-alone programs also look for and load prolog.ini. Runtime systems do not.

Typically, prolog.ini files are used to define file search paths, library directories, and term expansions.

If the +f option is specified, the initialization file prolog.ini is not loaded.